Arturo Casadevall, MD, PhD Chair, Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health Convalescent Plasma for Prophylaxis and Treatment of COVID19 Arturo Casadevall MD, PhD Johns Hopkins School of Public Health What is convalescent plasma? • Plasma is the liquid in the blood that holds the blood cells • It is obtained by separating the cells from the liquid • Differs from ‘sera’ in that it contains clotting factors • Can be obtained from donors by plasmapheresis • Obtained by standard transfusion practices Principles of Convalescent Plasma Usage Convalescent Serum (Plasma) used in past epidemics 1918 1934 1946 Specific Immunoglobulin (antibody) is the active component in convalescent plasma • Pathogen (virus) specific immunoglobulin develops during late disease and early convalescent period. • Immunoglobulin includes both IgM and IgG • IgG half-life about 20 days • Complex mixture of antibodies • Effective immunoglobulins • Neutralizing antibody • Non-neutralizing antibody mediates antiviral functions through IgG receptor (antibody-dependent cellular cytotoxicity, ADCC; phagocytosis, complement activation) Convalescent Plasma for coronavirus disease SARS Coronavirus (2003) Hong-Kong Study: 80 patients with SARS coronavirus infection treated with convalescent sera. A higher discharge rate among those treated with convalescen sera (58.3% vs 15.6%; P<0.001) MERS Coronavirus Anecdotal use – well tolerated but efficacy difficult to assess China uses Convalescent Plasma against COVID19 JAMA 2020 PNAS 2020 CHEST 2020 Italy Uses Convalescent Plasma against COVID19 Two Publications with Convalescent Plasma Information COVID19 Convalescent Plasma Protocol https://www.nbcnews.com/health/health-news/plasma-treatment- being-tested-new-york-may-be-coronavirus-gamechanger-n1178436 FDA Actions (www.fda.gov) • March 24 Compassionate use of convalescent plasma allowed • April 3, 2020. Hopkins granted permission of clinical trials of convalescent plasma in high risk individuals • April 3, 2020. FDA allows Expanded Access to Convalescent Plasma for the Treatment of Patients With COVID-19 • April 8, 2020. Recommendations for Investigational COVID-19 Convalescent Plasma (https://www.fda.gov/vaccines-blood - biologics/investigational-new-drug-ind-or-device-exemption-ide- process-cber/recommendations-investigational-covid-19- convalescent-plasma) Risks Known • Transfusion reaction • Infectious disease Theoretical • Antibody pro-inflammatory reaction Risk-Benefit analysis suggests Benefits >> Risk for all age groups. Bloch et al. JCI 2020 Current Status • Compassionate use being done USA • Many countries deploying convalescent plasma (UK, France, Italy, Spain, Argentina, Panama… etc) • Clinical trials in preparation Prophylactic use Early therapeutic use Late therapeutic use Pediatric protocol • Major problem – logistical Plasma is scarce commodity Donation Information Red Cross New York Blood Center Specific institutions (Mt Sinai in NYC, Methodist in Houston, Hopkins) ccpp19.org Closing thoughts Convalescent plasma history provides strong encouragement for use Convalescent plasma supported by strong theory of antibody action Plasma therapy is relatively safe (as safe as transfusion practices) Efficacy against COVID19 Anecdotal evidence and patient case series encouraging Need randomized control trials to know if, when and how to use Challenge today: LOGISTICAL, LOGISTICAL, LOGISTICAL…will get easier. .